Electric welding circuit timer



Oct. 26, 1937. E. G. BEIDERMAN 2,097,410

ELECTRIC WELDING CIRCUIT TIMER Filed March 27, 1934 5 Sheets-Sheet l I N VEN TOR. EDWARD G.BEIDERMAN A TTORNEY.

Oct. 26, 1937.

E. G. BEIDERMAN ELECTRIC WELDING CIRCUIT TIMER Filed March 27, 1934 3 Sheets-Sheet 2 l 12 P 1 3 E INVENTOR.

EDWAQD (1B2 1021mm ATTORNEY.

Oct. 26, 1937. E EIDERMA 2,097,410

ELECTRIC WELDING CIRCUIT TIMER Filed March 2'7, 1954 3 Sheets-Sheet 3 EDWARD GLBEIDERMAN.

BY M

ATTORNEY.

Patented Oct. 26, 1937 UNITED STATES ELECTRIC WELDING CIRCUIT THHER Edward G. Beidernian, Detroit, Mich, assignor to Edward G. Budd Manufacturing Company, Philadelphia, Pa., a corporation of Pennsylvania 7 Application March 27, 1934, Serial No. 717,977

3 Claims.

This invention relates to timing devices for electric circuits and is especially useful. for the timing of electric welding circuits.

Among the objects of my invention are the construction of a timer for an electric circuit and more particularlya welding circuit having a very small number of parts and ability to withstand the rigid use in production processes, the construction of a timer having accurate adjustability and timing and" simplicity in construction, the construction of an e1ectro-mechanical timer of few parts, theconstr'uction of a timer having a long operating life, accurate timing, accurate control and other objects not specifically enumerated.

I attain the foregoing and other objects of my invention by constructing an electric circuit timer comprising relatively movable contacts arranged to eifect the energization and de-energization of the circuit and cam means arranged to efiecta timed closure of said contacts.

My'invention will be better understood when considered in connection with the accompanying drawings wherein Fig. l is a front elevatlonal view,

Fig. 2 is a side elevational view,

Fig. 3 is a bottom plan view,

Fig. 4 is a fragmentary view of the operating cam and its armature.

Figs. 5, 6, and '7 are a partial front elevational view showing the switch operation.

Fig. 8 is a simplified and schematic wiring diagram showing the electrical connections of the parts.

Considering the drawings in more detail, the timing apparatus. of my invention is seen in front elevation in Fig. 1 comprising a base [0 of insulating material arranged for securement to any suitable support by means of the bolts ll. Mounted upon this base are the various component parts of the timing mechanism comprising contacts l2 arranged to effect the-energize.- tion and de-energization of the timed circuit, a timing solenoid l3 and armature I4, and cam means i5 in cooperating relation with the contacts l2 and the armature H to effect the timed energization of the circuit, and auxiliary equipment in addition to the solenoid l3 and its associated parts which upon operation of an initiating means eflects the energization of the solenoid. This latter equipment includes a relay I6, and a transformer 30 to reduce the applied voltage and may be housed within a single cover member ll. Although the relay alone is shown in Fig. 1 of the drawings in this position, it will be readily understood that these specific disclosures are for purposes of illustration and are readily subject to variation due to the needs and expediencies of the application or particular use of the device. e

from the remainder of the apparatus.

The relatively movable contacts l2 comprise the parts l8 and IS, the contact l8 being relatively fixed with respect to the base l0 and the contact I9 being relatively movable with respect to both the base and the contact [8. These contacts are mounted in insulated relation upon a bracket 20 which is secured to the base l0 by bolts 2| and dowel pins or other means 22. The insulated relation is obtained by means of a plurality of members comprising insulating material. One of these members comprises a substantially square sleeve 96 encompassing the arm 23 and positioned between the component parts of the arm 24. This arrangement effectually insulates the contact l8 and its correlated electrical parts The contact I9 is insulated from its arm 33 by means of insulating washers 91 and 90 and'a tube of insulating material 33. The electrical connection from lead 19 to contact I 9 is by way of a projection I00 upon the conducting angle member IM to which the contact I5 is secured. The tubes and washers effectually insulate this electrical part from the remainder of the apparatus. Other incidental insulating elements are the parts I02 and I03 comprising sheet insulating material which prevents any are at the contacts l8 and I9 from jumping to the electrically conducting parts of the apparatus. The bracket 20 is so arranged to provide an arm 23, of substantially square cross-section to which is rigidly secured a metal arm 24. At the extremity of this metal arm is pivotally secured the contact member 18 by means of a pin 25. This contact [8 is positioned in space in a yieldable manner by the spring 26 and the limit stop bolt which limits pivoting movement of the lever 28 at the point 25. A latching device 30 retains this limit stop member 21 in said position and adjustment can. be further accomplished by varying the operating characteristics of the spring 26 and the arrangement of the lever arms of the member 28 as well as adjustment of the bracket 3|. Electrical connection to contact I8 is attained through the terminal 32. Terminal l3.is likewise pivotally mounted upon bracket 20 and arranged to be relatively movable with respect to contact l0.

This is accomplished by the mounting of contact l3 at one end of the lever 33, at which end an electrical connection 3 is made. The lever 33 is pivotally secured by the pin 35 to the bracket 20 and pivots thereabout.

The bracket 20 is also provided with an extending portion 36 to which is secured an adjustable limit stop member 31 which adjustably 11mits the movement of the lever 33 about the pin 35. The adjustment of this limit stop member 31 predetermines the spacing of the contacts l3 and i9 while in disengaged position. This limit stop engages a projecting portion 33 on the lever 33. Where additional means are desired to assist rapid opening of the contacts and dissipation of inertias or" the parts, a further connection between the parts 33 and 3t may be made by a connecting pin 39 having collars or nuts til at the opposite extremities thereof, passing through suitable openings iii and s2 and a spring 433 which is adjustable both as to its inherent characteristics and properties and likewise with respect to the length of the pin 3e and its free length. The adjustable features herein named and the adjustable features with respect to the parts 26, 2'71 give multiple compensation and adjustment. To the extending portion M of lever 33 may, if desired, be added counter-weights in secured relation thereto, which weights may be used to effect rapid opening of the contacts and eliminate unbalanced forces. The description so far has been limited to the relatively movable contacts it and E9 and their movement and adjustment about the bracket 26. These two contacts efiect the energization of the circuit being timed and may preferably be directly in the circuit unless otherwise controllably associated therewith.

The immediate means for effecting the timed engagement of contacts 58 and it comprises the solenoid l3 and its armature i i. The solenoid is mounted rigidly against the base it and comprises the laminated core t5 and laminated armature it. To this laminated armature it is secured an armature extension member li which is relatively fixed in space by means of the bearing 68 of bracket 69, which bracket is likewise secured to base Hi by bolts 2i and dowel pins 22. At the lower end of the armature All are adjustable members comprising a bolt 59 and lock nut 59 arranged for screw threaded engagement 52 with the armature ill. This adjustment may, if desired, be such as to engage the projecting arm (it of the lever 33 if the contacts l8 and it should stick and provide a hammer blow to additionally open the said contacts. These adjustable elements may be adjusted in such a manneras to preclude engagement under normal operation and to only engage the said parts under conditions of adverse operation such as the said sticking of the contacts, the normal operation being such that the contacts open of their own initiative after the cam engagement is complete.

Further inertia devices comprise the spring mechanism 58 and its component parts at the top of the solenoid to absorb inertias at the completion of the upward stroke, which spring is likewise adjustable both asto its characteristics and to its adjusted relation in position. Upon the armature ll may likewise be secured the bracket 56 having an adjustable means 55 and 56 for engagement with the member 5? which is secured to the bracket 39 and may comprise v shock absorbing mediums such as rubber or some other means. It should be readily understood that the shock absorbing mediums may likewise take other forms, for example dash pots or such other means as are suitable, although the disclosed construction has been found entirely satisfactory.

interconnecting the. armature H3 and the contacts i2 is a cam means flt'eifecting the engagement of the contacts when the armature it operates. This means comprises a cam member 58 secured to the lever 33 and a cam member 59 secured to armature ll. The cam memher as has a control surface so which deter-nee the timing engagement of the contacts. This surface maybe longer or shorter and may be spaced nearer or farther away from the cam member'59 in its position in space. member 59 is preferably secured to armature ll by a pivotal connection. Such a-connection in one form is by means of a pin Hi5 which has 2. suitable connection with the part fill and is secured thereto by a set screw we. Obviously other arrangements may be utilized, although this connection has been found satisfactory. Positioned about the pin N35 is a spiral spring iil'l'which may be connected to pins H36, N39, or the springs themselves may have extending terminal portions which may be received in slots at these locations. The cam 59 may preferably have a hardened roller H0, although other arrangements can as readily be used. The cam" and pin are so associated with the armature by means of a depression or slotted portion Hi,

The cam which portion has a defining side Wall provid- 3 ing a limit stop H2 and a diagonally extended wall portion M3 to facilitate the operation of the cam as Well as to limit its pivotal motion about its axis. The cam 59 engages cam 58' during upward movement and operates the timer but on the return stroke the cam 59 pivots and rides freely by cam 58.

Adjustment of contact It further to the right in its position in space will provide a longer contact-period between the parts i8 and it with respect to the position in time of cam engagement, whereas the position of the said contact it further to the left provides a shorter period of contact engagement under the influence of the cams. Adjustment of the limit stop 3'11 may position contact 09 closer or farther away from the contact it in its disengaged spaced position. This adjustment extends or shortens respectively the period intervening between the beginning of motion by cam 59 and its engagement with cam surface 65. The engagement of contacts i8 and it may be arranged for short or long periods of engagement or spaced relation of non-engagement, either before or after cam engagement, or during cam engagement and/or independently of the cam surfaces or by means of the cam surfaces and/or combinations thereof.

. The timing of the apparatus readily follows as actuation of solenoid '83 moves armature and through the intermediation of cams i5 closes contacts it. This effects the timed energization and effective termination of the energization of the circuit. The solenoid I! 3 may be operated directly or through transformer connections from the main power line and its energization and deenergization may be controlled from an initiating means in the nature of 'a push button, treadle or pressure operated switch upon or associated with the electrodes. The solenoid it may be preferably connected through the interposition of potential transformers reducing the voltage from the power lines to a low control equipment voltage to insure safety to operators aswell as to materially limit the danger of damaged equipment. In any event the solenoid should be cohnected to a source of substantially constant voltage so as to have a substantially constant tim cycle of operation.

One manner of electrically connecting the f timer for operation is shown in Fig. 8. Ahand by the timer. Associated with the cylinder M, is a pre operated switch 12 having leads it sure the electrode elements I6 and H are forced together upon the work. when this electrode engagement with the work reaches the proper predetermined such. engagement, the pressure operated switch 12 will be actuated and in turn cause the timer to operate and send a welding.

impulse through the welding circuit which comprises a primary circuit 80 of welding transformer 8| having primary and secondary windings 82 and 83, respectively, the secondary 83 being connected by leads 84 to the electrodes 16 and 11. One of the primary leads 88 connects the transformer to the power source 18 and the other lead 80 passes through the contacts l8 and I8 to the other side of the power source by means of the line 18. Withthe connection shown, the solenoid I8 is operated by the closure of the circuit from relay It to contacts 88' and 8|. This arrangement is such that the control circuit is of low voltage. The circuit of relay i6 is connected manner.

to the low voltage side of a transformer 88 hav ing a high voltage primary 8| of'possibly 220 volts and a low voltage secondary 82 of possibly 15 or 20 volts. This secondary is connected through leads l4 and 83 to the pressure operated switch I2 and the one side of the relay I6, the other connection of relay i8 being by means of lead 78 to the switch. This arrangement of connections can be materially simplified if it were desired to have the solenoid it operated directly from the switch 12, under which circumstances an equivalent operating circuit would be made by connecting lead l8 to terminal "84 of solenoid l3, allowing terminal 85 to remain connected by lead 86 and the terminal 81, and connecting terminal 88 directly to lead 14. Under this set of connections the relay l6 and transformer 88 '40 would be eliminated, but there would behigh voltage in the control circuits which is to be avoided, if possible. The illustrated connections are preferable and provide low voltage. The primary of transformer 80 is connected by leads 84 and 85 to terminals 81 and 88. A second circuit of main line voltage connects terminal 81 by lead .86 to terminal oi solenoid l8, and by lead 88 connects terminal 88 to contact 80', the circuit being completed by lead 88 connecting contact 8! to terminal Bl.

' The operation of the timer is in the following The electrodes being positioned with respect to the work and engagement having been made, switch 12 operates due to air pressure conditions or is a push button or treadle operated switch or some other means arranged to effect energization of relay l6 which in turn closes contacts 80' and 8| energizing the circuit of solenoid l3. Relay i6 is illustrated in the wiring -diagramas having a movable contact and a fixed contact providingrelatively movable contacts thereby. but can equally well be of the type shown in Fig. 1 wherein there is provided a movable armature I'll which engages the two contact elements H5. Any other suitable form of relay may equally well This in turn raises armature l4 and causing a consequent engagement of the cams 58 and in their turn eil'ect a timed'engagem'ent of contacts l8 and I8, closing the primary circuit of the welding transformer 8| and passing an impulse of effective welding energy from the leads 8 to the electrodes l6 and I1. The apparatus automatically .re-sets itself and is ready for a consequent second welding operation, .and in practice these devices direction of movement the cam is ineffective to close the contacts l8 and I 8.

I aim to cover the generic spirit of my invention by the hereto appended claims wherein the specific terminology is not to be construed as a limitation, but merely as a circumspective form of definition.

What I claim is:

1. A timing device for electric circuits comprising a pair of pivotally mounted contacts in said circuit biased to open position, one of said contacts being relatively fixed but having fine adjustment means for adjusting its distance from the other contact and means yieldingly biasing it toward the other contact, the other contact being biased away from the first contact and having fine adjustment means for adiusting its position with respect to the firstnamed contact, a cam associated with said last named contact and a rectilinearly movable cam actuator, timing solenoid and armature means for actuating said rectilinearly movable cam into engagement with said first cam to close the contacts for a constant predetermined time each time the'solenoid is actuated, depending upon the distance between the contacts, the adjusted relation of the cams, and characteristics of the solenoid and armature.

2. A timing-device for electric circuits comprising a pair of pivotally mountedcontacts in said circuit biased to open position, said contacts having fine adjustmentv mea'ns associated therewith to adjust the distance between the contacts when in open position, a cam device associated with one of said contacts, a rectilinearly movable actuator having a predetermined time constant and carrying a cam device for engagement with the cam device of said contact and active in one direction of movement of the actuator to time the closing of the circuit through said contacts, but inactive to operate the contact on the reverse movement, fine adjustment means for adjusting the relative position of said cam devices to prising relatively movable contacts in the circuit,

cam means arranged to eifect closure of said contacts, a reciprocating actuator arranged to effect the operation of said cam means, said cam means arranged to be effective in one direction of movement of said actuator and non-effective in the opposite direction of movement thereof, time-controlled means for moving said actuator in its actuating movement each time at the same predetermined speed for uniform timing of the'successive closures of the circuit. and means operable in the closed position of said contacts to elect a positive opening of the contacts in the return movement of the actuator.

EDWARD G. BEIDERMAN. 

